The present invention generally relates to semiconductors, and more specifically to a module substrate that allows replacement of faulty semiconductor chips, a semiconductor module having the same, and a method for manufacturing the semiconductor module.
In general, semiconductor chips are packaged into various types such as a BGA (ball grid array) type, an LOC (lead-on-chip) type, a CSP (chip size package) type, and so forth, and are then mounted to PCB (printed circuit board) substrates and constitute modules.
Recently, a DCA (direct chip attachment) type has been proposed, in which non-packaged semiconductor chips are directly mounted to a PCB substrate so as to increase the mounting density of semiconductor chips and improve electrical characteristics. In the DCA type, after the semiconductor chips are bonded to the substrate, adhesive members or underfill members are formed between the substrate and the semiconductor chips in order to prevent joints between the semiconductor chips and the substrate from being damaged during testing or handling. However, since the semiconductor chips cannot be detached from the substrate, a faulty semiconductor chip cannot be appropriately replaced. The faulty semiconductor chip may be detected because it failed a test. Accordingly, the faulty semiconductor chip may also be referred to as a failed semiconductor chip.
In order to cope with this problem, a method of additionally providing a redundancy chip for replacing the failed semiconductor chip is generally known in the art. While this method is advantageous in terms of manufacturing yield, additional space is needed for mounting the redundancy chip. Further, as an area to be used for design is limited, the number of redundancy chips capable of being mounted is also limited. Therefore, in the case where a number of failed semiconductor chips exist in one semiconductor module, the desired improvement of manufacturing yield may be impeded. Moreover, because additional circuit wiring lines are needed to connect the redundancy chips, the design of the circuit wiring lines are complicated.